Electric switch.



G. SWEETSER.

ELECTRIC SWITCH. APPLIUATION FILED Nov. a0, 1909.

Ptnd Dec. 2o, `1910.

Ey'fa GEORGE SWEETSER, OF LONDON, ENGLAND.

. v I Specification of'iLetters Patent.

ELECTRIC SWITCH.

Patented Dee. 2o, 1910.

. Applicationled November 30, 1909. Serial No. 530,682.

To all 'whom tima concern:

Be it known t at I, GEORGE SwEETsER,

who am not a' citizen of the United States,

- residing at Eastgate, Ledringtony Road, Up-

per Norwood, in the county of London, England, have invented c ertaln new and useful Improvements in Electric Switches, of which the following is a specification.

The .main object of this invention is the production of quick-make and quick-break electric thermal switches that shall be morev simple and efficient than heretofore.

. in each position. i

A, Fig. 1 is the thermal expansionrod or y A'thermal switch, for automatically opening and closing an electric circuit, made according to this invention is provided with a bracketv or standard having an internally grooved opening; in this opening is sprun a thin metal plate orspring contact, buckle or bowed out on one side so as to be capable of being snapped back or .forth Vacross its central position. This buckled or bowed plate may 'be' actuated, by suitable connections to any of theexpansion rods, strips, or bimetallic strips now in use, but preferably by the'device shown in the accompanying drawings of which- A Figures 1 and 2 are front and side eleva-- tions of a.,multiplyin lever motion device; ments 'and Fig. 5

e ate Figs. 3 and/.t are en arg? a section showing the buc l d or bowed p tube wound with .wire carrying a current, andv engaging the sh'ort end of .the lever B, the long end ofV thelever being forked, onev prong of whichextends on each side of the buckled plate C which in its normal or closed position is. in electrical, contact with one prongof the forked lever by the contact E.

Upon the current expanding the rod' A, the.

forked end of the leverpushes the buckled plate over until it is past its central position, when the plate snaps freely over on to an insulator on the other prong, the heating coil,

lever, and buckled plate being electrically 'connected -in series, the circuit is thus opened; and upon vthe cooling of the eX- pansion rod, the spring D snaps the buckled plate back to itsfrst posit-ion. By substituting an insulated lcontact F for the insulator on the forked end of the lever, another circuit can be controlled.

Having now particularly described and ascertained the nature of my said invention,`

and in what manner the same is to be performed, I declare that what I claim is- An electric thermal switch comprising an .electric thermal expansion device, a bowed contact plate and a forked lever oscillatedv by said expansion deviceh having its forked same, and contacts carried by said forked lever. fl,

In .testimony whereof, may. slgnaf ture in 'presence of two witnesses.

GEORGE swEETsER.

' Witnesses:

R. WEsTAco'rr, H. D. JAMESON.

end straddling the plate so as to snap thev 

